111 research outputs found

    Modeling price dynamics on electronic stock exchanges with applications in developing automated trading strategies

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    This thesis develops models for accurate prediction of price changes on electronic stock exchanges by utilizing autoregressive and logistic methods. Prices on these electronic stock exchanges, also called ECNs, are solely determined by where orders have been placed into the order book, unlike traditional stock exchanges where prices are determined by an expert market maker. Identifying the significant variables and formulating the models will provide critical insight into the dynamics of prices on ECNs. Whereas previous research has relied on simulated data to test market strategies, this analysis will utilize actual ECN data. The models recognize patterns of asymmetry and movement of the shares in the order book to formulate accurate probabilities for possible future price changes. On traditional stock exchanges, price changes could only occur as quickly as human beings could enact them. On ECNs, computerized systems place orders on behalf of traders based on their preferences, resulting in price changes that reflect trader activity almost instantaneously. The quickness of this automation on ECNs forces the re-evaluation of commonly held beliefs about stock price dynamics. Previous strategies developed for trading on ECNs have relied mainly on price fluctuations to gain profits. This thesis uses the formulated models to design profitable strategies that use accurate prediction rather than price variability

    The Grizzly, February 13, 1987

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    Greek Life Grits Teeth at State\u27s Hazing Law • Free Roses for Lorelei • Letter: Fellow Student Reports on Chang • News Notes: R.A. Selection Underway; St. Andrew\u27s Scholarship; National Women in Sports Day • Bears Bump LaSalle and Haverford, Racich Wins 100th • Udovich\u27s Career High Leaves Bears to 74-69 Win • Mer Men\u27s Streak Ends vs. Loyola • Gymnastics Takes Fourth Win • Track Men Break Records • Swimmin Women on Warpathhttps://digitalcommons.ursinus.edu/grizzlynews/1181/thumbnail.jp

    The Ecology of Individuals: Incidence and Implications of Individual Specialization

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    Most empirical and theoretical studies of resource use and population dynamics treat conspecific individuals as ecologically equivalent. This simplification is only justified if interindividual niche variation is rare, weak, or has a trivial effect on ecological processes. This article reviews the incidence, degree, causes, and implications of individual-level niche variation to challenge these simplifications. Evidence for individual specialization is available for 93 species dis- tributed across a broad range of taxonomic groups. Although few studies have quantified the degree to which individuals are specialized relative to their population, between-individual variation can some- times comprise the majority of the population’s niche width. The degree of individual specialization varies widely among species and among populations, reflecting a diverse array of physiological, be- havioral, and ecological mechanisms that can generate intrapopu- lation variation. Finally, individual specialization has potentially im- portant ecological, evolutionary, and conservation implications. Theory suggests that niche variation facilitates frequency-dependent interactions that can profoundly affect the population’s stability, the amount of intraspecific competition, fitness-function shapes, and the population’s capacity to diversify and speciate rapidly. Our collection of case studies suggests that individual specialization is a widespread but underappreciated phenomenon that poses many important but unanswered questions

    Uncovering Tropical Eiversity: Six Sympatric Cryptic Species of Blepharoneura (Diptera: Tephritidae) in Flowers of Gurania spinulosa (Cucurbitaceae) in Eastern Ecuador

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    Diversification of phytophagous insects is often associated with changes in the use of host taxa and host parts. We focus on a group of newly discovered Neotropical tephritids in the genus Blepharoneura, and report the discovery of an extraordinary number of sympatric, morphologically cryptic species, all feeding as larvae on calyces of flowers of a single functionally dioecious and highly sexually dimorphic host species (Gurania spinulosa) in eastern Ecuador. Molecular analyses of the mitochondrial cytochrome oxidase-I gene from flies reared from flowers of G. spinulosa reveal six distinct haplotype groups that differ by 7.2-10.1% bp (uncorrected pairwise distances; N = 624 bp). Haplotype groups correspond to six distinct and well-supported clades. Members of five clades specialize on the calyces of flowers of a particular sex: three clades comprise male flower specialists; two clades comprise female flower specialists; the sixth clade comprises generalists reared from male and female flowers. The six clades occupy significantly different morphological spaces defined by wing pigmentation patterns; however, diagnostic morphological characters were not discovered. Behavioural observations suggest specific courtship behaviours may play a role in maintaining reproductive isolation among sympatric species

    Created mangrove wetlands store belowground carbon and surface elevation change enables them to adjust to sea-level rise

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    Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr(-1)), with surface elevation change of 4.2-11.0 mm yr(-1) compared with 1.5-7.2 mm yr(-1) for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100

    The Grizzly, February 6, 1987

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    Residential Village Saluted: Ursinus Recipient of County Planning Award • Art Critic Kuspit Condemns Ursinus\u27 Acquisitions • Biology Dept. Offers Field Study • Letters: Pro Abortion Bias Suggested; Art Critic Elitist; Hoopsters Accomplish Goals Despite Poor Press; Kane Commends McCullough • News Notes: Weaver to Play on Heefner Organ Again; Board Member Jeffers Dies at 79; Health Promotion Project; Lorelei, a U.C. Tradition • The Coddling of College Students • Connolly Finds Berry Piece Arrogant, Rash and True • Grappling Bears Stun Opponents in Streaking to 9-2 • Ursinus Roars Back to Thrash Hopkins • Men\u27s Track Impressive Early in Season • Mer Men Waiting for Loyola • Lady Hoopsters Capture First Home Win • Sophomore Wrestler Seislove on a Roll • A Baby and the Ball - Two Plays Called at Once • Japanese Program Offered Again • Fishing Club Factshttps://digitalcommons.ursinus.edu/grizzlynews/1180/thumbnail.jp

    The Grizzly, October 31, 1986

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    NCAA Drug Tests Bar All but Natural Highs • History in the Making: U.C. Hosts 1st Big Rock Concert Since Hooters \u2782 • Heefner Organ Pumps New Life Into Founder\u27s Day Rites • Letter: It\u27s All in Your Point of View • Hess Encourages Financial Aid Applicants • Jazzing It Up With Branker • Scope of New Course Broadens Science Offerings • Fear of Mosquitoes and Sex? AIDS Expert Tells What\u27s Next • Akin Follows Losing Teams; Laments Vanished Baseball Dream • C & C to Focus on Scientific and Economic Ideologies • Despite Bad Food and Lack of Beer Freshman Say, We Like It Here. • Grizzlies Clash with Stubborn Mules After Kicking Away at G-burg and \u27Nova • Lady Sticklers Stuck at 8-7 After St. Joe\u27s Loss • Sox Go Home Sans Joy Red Cross(e) Knight Named Series MVP • O\u27Donohue and Haux Power Lady Runners to PAIAW Championship • Ursinus Harries Race to a 5-0 Start • Volleyball\u27s Doleniak Back in Action • Win a VCR. Put Your Foot Where Your Mouth ishttps://digitalcommons.ursinus.edu/grizzlynews/1173/thumbnail.jp

    The Lantern Vol. 53, No. 1, Fall 1986

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    • Living In-Sanity • Sentence of Dawn • Addict • Where Do They Come From? • Midnight Hags Astride • Escape • Here I Sit • A Minor Key • To Picasso\u27s Old Guitarist • Nothing More • Love or Futility • A Few Inches • My Only Gift • Reserved • A Message to a Disillusioned Friend • Doing it the Hard Way • The Wall • A Look Ahead at a Look Behind • Fantasy Secret • Lisa • Caesar\u27s Last Words • There\u27s a Grouse in My House • If You Want Me • The Education of a Samaritan • Death of Illusion • I Walked and Pondered • A Woman Walked Past Him and He Smiled • Betrayal • Blindness • Innocence Unveiled • Amandahttps://digitalcommons.ursinus.edu/lantern/1129/thumbnail.jp

    The Vehicle, Fall 2010

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    Table of ContentsPoetryFill Your Mouth with BerriesAaron Whitepage 1 RelationsJamie Van Allenpage 2 ExodusMegan Marie Olsonpage 4 Single FileRashelle McNairpage 7 The Aesthetic Value of the Moon, by CandlelightKathy Deckerpage 15 FactalsGabrielle Keigherpage 16 Day 5David Jacksonpage 17 Esta LloviendoHeather Gerrishpage 19 FacebrokeDarrin Gordonpage 23 5:08 pmNikki Riechertpage 24 Train TunnelsAshton Tembypage 34 VariationsKathy Deckerpage 35 WantRashelle McNairpage 36 FriendshipScott Maypage 37 Golden LandJacob Swansonpage 38 Last Night I DreamtAshton Tembypage 39 Smallest GestureScott Maypage 44 Somebody\u27s Hut in MexicoGinamarie Lobiancopage 45 Some Things You Just Can\u27t Tap Dance AroundClint Walkerpage 53 Prose Lamparus de DiosAaron Whitepage 8 Learning CurveScott Maypage 18 RocktonKatelyn Pfaffpage 20 Fatal DistractionSolomohn Ennispage 25 Noodle NonsenseGabrielle Keigherpage 41 AntarcticaMichael Payeapage 46 Special Features James K Johnson Award Winners: God is GraciousJohn Klyczekpage 57 To My Ever Growing ChestJennifer Hindespage 74 God\u27s ScapegoatJennifer Hindespage 76 Rape (Verb, Noun)Jennifer Hindespage 78 Featured Artist: Ashton Tembypage 81 Editor\u27s Pick: The Shooter by Patrick Hallpage 87 Chapbook 2010 Author:Kim Hunter-Perkinspage 114 About the Contributorspage 118 About the Editorspage 122https://thekeep.eiu.edu/vehicle/1092/thumbnail.jp

    The Vehicle, Fall 2010

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    Table of ContentsPoetryFill Your Mouth with BerriesAaron Whitepage 1 RelationsJamie Van Allenpage 2 ExodusMegan Marie Olsonpage 4 Single FileRashelle McNairpage 7 The Aesthetic Value of the Moon, by CandlelightKathy Deckerpage 15 FactalsGabrielle Keigherpage 16 Day 5David Jacksonpage 17 Esta LloviendoHeather Gerrishpage 19 FacebrokeDarrin Gordonpage 23 5:08 pmNikki Riechertpage 24 Train TunnelsAshton Tembypage 34 VariationsKathy Deckerpage 35 WantRashelle McNairpage 36 FriendshipScott Maypage 37 Golden LandJacob Swansonpage 38 Last Night I DreamtAshton Tembypage 39 Smallest GestureScott Maypage 44 Somebody\u27s Hut in MexicoGinamarie Lobiancopage 45 Some Things You Just Can\u27t Tap Dance AroundClint Walkerpage 53 Prose Lamparus de DiosAaron Whitepage 8 Learning CurveScott Maypage 18 RocktonKatelyn Pfaffpage 20 Fatal DistractionSolomohn Ennispage 25 Noodle NonsenseGabrielle Keigherpage 41 AntarcticaMichael Payeapage 46 Special Features James K Johnson Award Winners: God is GraciousJohn Klyczekpage 57 To My Ever Growing ChestJennifer Hindespage 74 God\u27s ScapegoatJennifer Hindespage 76 Rape (Verb, Noun)Jennifer Hindespage 78 Featured Artist: Ashton Tembypage 81 Editor\u27s Pick: The Shooter by Patrick Hallpage 87 Chapbook 2010 Author:Kim Hunter-Perkinspage 114 About the Contributorspage 118 About the Editorspage 122https://thekeep.eiu.edu/vehicle/1092/thumbnail.jp
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